Graphic arts film dryer

ABSTRACT

A cabinet having an inlet opening and an outlet opening, and a series of pairs of rolls gripping the film in an intermediate plane and carrying it through. Each roll is made up of a plurality of axially spaced sections, the sections of the rolls of each pair being transaxially aligned and inter-engaging or mutually gripping. The roll sections of successive pairs are relatively offset or staggered, with the respective rolls overlapping or interfitted. The rolls include two groups of main rolls of the above kind, each group including a plurality of pairs, and the rolls in the two groups are relatively offset axially. Also included is a pair of changeover or transfer rolls, each made up of a plurality of sections of lesser axial extent than the sections of the main rolls, and interfitted with the adjacent rolls of the two groups of main rolls.

Wnited States Patent [191 Edgington et al.

[ 1 Apr. 2, 1974 GRAPHIC ARTS FILM DRYER [76] Inventors: Donald C. Edgington; William E.

Edgington, both of 2425 N. Ashland Ave., Chicago, [11. 60614 221 Filed: on. 30, 1972 21 Appl. No: 301,792

FOREIGN PATENTS OR APPLICATIONS 3/1959 Germany 34/162 Primary Examiner-William F. ODea Assistant Examiner-Paul Devinsky Attorney, Agent, or Firm-Paul H. Gallagher [5 7] ABSTRACT A cabinet having an inlet opening and an outlet opening, and a series of pairs of rolls gripping the film in an intermediate plane and carrying it through. Each roll is made up of a plurality of axially spaced sections, the sections of the rolls of each pair being transaxially aligned and inter-engaging or mutually gripping. The roll sections of successive pairs are relatively offset or staggered, with the respective rolls overlapping or in tel-fitted. The rolls include two groups of main rolls of the above kind, each group including a plurality of pairs, and the rolls in the two groups are relatively offset axially. Also included is a pair of changeover or transfer rolls, each made up of a plurality of sections of lesser axial extent than the sections of the main rolls, and interfitted with the adjacent rolls of the two groups of main rolls.

5 Claims, 9 Drawing Figures PAIENIEBAFR 2 m4 3800.434

SHEET 1 (IF 3 PATENTEU APR 2 I974 SHEET 2 0r 3 MTENTEU 2974 SHEU 3 BF 3 GRAPHIC ARTS FILM DRYER PERTINENT PRIOR ART US. Pat. No. 3,557,469, issued Jan. 26, 1971, to the present Donald C. Edgington.

FIELD OF THE INVENTION The invention resides in the general field of graphic arts and relates particularly to drying films after they have been washed. The dryer includes rolls acting as squeegee rolls and operating to grip and convey the film through the dryer. The dryer also includes means for driving a drying current of air therethrough. The above-mentioned patent is directed to this general field.

OBJECTS OF THE INVENTION A broad object of the invention is to provide a novel dryer of the foregoing general kind.

Another object is to provide a dryer of the foregoing general kind having a novel arrangement of rolls which produce greater squeegee action, and more effectively prevent the film from wrapping around the rolls as otherwise tends to happen because of the wetness of the film.

A further object is to provide means for preventing wrapping of the film around the rolls which include the novel arrangement of rolls having offset or staggered sections that relatively overlap or interfit.

A still further object is to provide means of the kind referred to, in which the rolls are arranged in two groups and in which the roll sections are relatively offset axially in the groups for producing more effective and complete squeegee action.

DESCRIPTION OF A PREFERRED EMBODIMENT In the drawings:

FIG. 1 is a longitudinal, vertical sectional view of a dryer made according to the present invention;

FIG. 2 is a top view of the set of rolls in the dryer, taken approximately at line 22 of FIG. 1;

FIG. 3 is an enlarged detail view of a center portion of the rolls shown in FIG. 2;

FIG. 4 is a front view of a portion of the rolls, showing several sections on each of the exposed rolls;

FIG. 5 is a sideview largely diagrammatic in nature oriented according to FIG. 1 and showing a portion at the left hand of FIG. 1;

FIG. 6 is a view of the drive for the rolls;

FIG. 7 is a detail of a fragment of the outlet end portion of the dryer, oriented in direction according to FIG. 1;

FIG. 8 is a schematic view of one form of means for producing a drying air current; and

FIG. 9 is a schematic view of another form of means producing a drying air current.

Referring in detail to the drawings, attention is directed first to FIG. 1 showing the dryer as a whole at 12 which includes a cabinet 14 here indicated diagrammatically. The cabinet has an inlet opening 16 and an outlet opening 18 both extending transversely across the cabinet. The arrows 20 indicate the direction of movement or conveyance of the film 21 through the dryer.

FIG. 1 alsoshows semi-diagrammatically the rolls in the dryer indicated'in the aggregate at 22 and reaching from adjacent the inlet opening to a position closely adjacent the outlet opening. The rolls include two sets 24, 26 located respectively above and below a central transverse horizontal plane 28 which extends through the inlet opening 16 and the outlet opening 18.

The rolls indicated in the aggregate 22 additionally include two main groups, 30, 32, arranged in a plurality of pairs as explained below, and a single pair of changeover or transfer rolls 34 between the two main groups, and preferably located centrally of the dryer in foreand-aft direction. Each pair of rolls includes vertically associated rolls, both in the groups of main rolls, 30, 32 and the changeover or transfer rolls 34.

All of the main rolls in the groups 30, 32 are identical, but the rolls 34 distinguish therefrom in the smaller axial extent of the sections making up the rolls. All of the rolls, both main and transfer, are preferably of the same diameter.

Each of the main rolls 22 (FIGS. 2 and 4) includes a shaft 36 and a plurality of sections 38 of rubber or rubber-like resilient and friction material mounted on the shaft. The sections 38 are identical in axial extent and spaced apart a distance similar to that same axial dimension, but slightly greater. Each pairv of the main rolls includes one above and below the central plane 28. For convenience two of these pairs are identified (FIG. 1) at 22a and 22b. In the case of each pair the sections 38 are vertically or transaxially aligned and they interengage at the plane 28 and grip the film therebetween and convey it through the dryer.

The sections 28 of the second pair 22b are offset relative to those of the first pair 22a a full axial dimension of the sections and are positioned for overlapping or interfitting relative to each other, i.e., the sections of each roll are interfitted with the sections of the adjacent roll. The rolls are offset or staggered in the manner stated throughout the succession of rolls, alternately from one pair to the next.

As indicated above, the spacing between the sections on a roll is only slightly greater than the axial dimension of each section so as to have a non-interference or sliding movement. The degree to which each section extends into the space between the two sections of the adjacent roll is not critical, and for convenience it may be nearly to the shaft of the next roll.

In feeding a film through the dryer, for drying it, the leading edge is introduced through the inlet opening 16 and fed to the bight between the first pair of rolls. These rolls convey the film therebeyond and into the next pair, and from the next pair into the third pair, etc., through the dryer.

Because of the overlap or interfitting of the sections of successive pairs of rolls, the film is prevented from wrapping around either of the rolls of a pair, because as the film leaves one pair, it is gripped by the next pair before it can follow around either of the rolls of the previous pair. This overcomes the tendency for this to happen by the wetness of the film, and this action proceeds throughout the full succession of the rolls.

The main rolls 30, 32 provide a squeegee action in gripping the film and conveying through the dryer, forcing the water from the film, but because of the spacing between the sections in adjacent rolls, which is only slight to prevent rubbing or abrasive action, there is a tendency for a line of water to remain on the film in line with the spacings as the film proceeds through the dryer.

To overcome this phenomenon the two groups of main rolls 30, 32, as groups, are offset or staggered one-half the axial dimension of one section of the rolls, so that the lines that may be formed in the first group 30, would be directly in line with the center of the roll sections in the group 32. However in order to maintain the overlapping or interfitting of the rolls as between the two groups, the changeover or transfer rolls 34 are provided. These rolls constitute a pair, i.e., one above and the other below the central plane 28, and each includes a plurality of sections 40 which are one-half the axial dimension of the sections 38 of the main rolls, and these changeover rolls are positioned to overlap or interfit with the sections of the adjacent rolls of the two groups of main rolls, 30, 32. The changeover rolls 34 therefore prevent the film from wrapping around the last roll of the group 30 and assist in conveying the film into the first pair of rolls of the group 32. Accordingly, the film proceeds from the first group to the second group of main rolls with the same continuity of control, and the lines as between the roll sections of the first group encounter the centers of the sections of the second group.

The number of rolls in each group may be as desired, such as six as here disclosed, according to practical considerations in removing certain quantities of water in performing the total drying operation.

As the film reaches the final set of rolls 22, identified as 22c (FIG. 7) the film is totally dry and there is no tendency, because of wetness, for the film to wrap around either of the rolls, but there occasionally is a tendency to so wrap around because of static electricity, and to prevent such an event fingers 42 are provided, mounted on the wall of the cabinet 14 and extending into the spaces between axially adjacent sections of a roll to a necessary extent, such for example as possibly a minimum beyond the surface of the final rolls 220, these fingers then maintaining the film in straight movement out through the exit opening 18.

The rolls may be driven by any suitable means such as shown in FIG. 6 which includes a common worm 44 working with worm gears 46 on the ends of the shafts 36 of the rolls, thus maintaining identical speed of rotation and corresponding peripheral movement of all the rolls.

The dryer also includes means for producing a drying current of air, such as disclosed in the above patent, although it may take any of various forms such as indicated diagrammatically in FIGS. 8 and 9. In FIG. 8 a blower 48 develops an air current, which may be heated, moving through a conduit 50 leading to branches 52 in turn leading to outlet air pipes 54 which are located in a cabinet 14. These air pipes 54 may be located as desired and provided with the desired number of nozzles for producing blasts of air on the film, the air tending to proceed opposite the direction of movement of the film and exit through the inlet opening 16.

In the other form of means for developing a drying air current, as represented in FIG. 9, a draft blower 56 is provided, connected with conduits 58, 60 communicating with the cabinet at the entrance end of the latter. Regardless of the exact form of air producing means utilized, the air draft passes through the various rollers and into direct contact engagement with the film.

In FIG. the rolls 22 are shown in large form where it will be seen that spaces 62 are formed between adjacent rolls as viewed axially. These spaces 62 curve both above and below the plane 28 or the film 21 and the drying current of air is enabled to engage the film on both sides. There is of course space between longitudinally aligned roll sections, such as identified as 22d, 22e in FIG. 5, this space being indicated at 64, and the air is enabled to pass between those two roll sections 22d, 22e and through the spaces 62 to the next opening axially displaced, and passing then longitudinally to the entrance opening or to the next pair of rolls, as the case may be.

The form of producing an air current in itself is not of the essence of the present invention, as indicated above, and any of various forms may be used, but it is pointed out that the arrangement of the rolls is such that the air current is enabled to flow freely between the roll sections and proceed from the exit end of the dryer to the entrance end and out through the entrance opening 16 in flow counter to the movement of the film.

We claim:

1. A film dryer comprising,

a cabinet having an inlet opening and an outlet opening at opposite ends,

a set of rolls each above and below a common plane passing longitudinally through the inlet opening and the outlet opening, the rolls together extending from adjacent the inlet opening to adjacent the outlet opening,

all of the rolls being of the same diameter, and all having peripheral surface portions at said common plane, and respective ones of the two sets interengaging at said plane as specified hereinbelow,

each of the rolls being made up of a plurality of axially spaced sections,

the rolls being arranged in pairs, each pair consisting of one roll in each of said sets, the sections of the rolls of each pair being transaxially aligned perpendicular to and interengaged at said plane,

the sections of longitudinally next adjacent rolls in each set being relatively offset axially and overlapping and interfitted, and each set of rolls including two groups spaced longitudinally, the sections of the rolls in each group being arranged respectively in longitudinal lines, and the aligned sections of the rolls of the two groups being offset axially a distance less than the axial length of a section and the dryer including means for flowing a stream of drying air through the cabinet.

2. A film dryer according to claim 1 wherein each of the sets of rolls includes a plurality of main rolls, and the sections of the main rolls are all substantially of the same axial length and spaced apart a distance greater than that length but only slightly so as to provide play between interfitted sections.

3. A film dryer according to claim 1 wherein each set includes a changeover roll between said two groups thereof, the sections of the changeover roll being of lesser axial extent than the sections of the rolls of said groups and overlapping and interfitted with the sections of the next adjacent rolls of said groups.

4. A film dryer according to claim 3 wherein the sections of the rolls of the groups are all substantially of the same axial length, the axial offset relation of the aligned rolls of the two groups is substantially one-half that length, and the sections of the changeover roll are substantially one-half that length axially.

tioned between the sections of said terminal pair of rolls, above and below said plane, and extending along that plane beyond the peripheral surface portions of the roll sections that are most adjacent the outlet opening. 

1. A film dryer comprising, a cabinet having an inlet opening and an outlet opening at opposite ends, a set of rolls each above and below a common plane passing longitudinally through the inlet opening and the outlet opening, the rolls together extending from adjacent the inlet opening to adjacent the outlet opening, all of the rolls being of the same diameter, and all having peripheral surface portions at said common plane, and respective ones of the two sets interengaging at said plane as specified hereinbelow, each of the rolls being made up of a plurality of axially spaced sections, the rolls being arranged in pairs, each pair consisting of one roll in each of said sets, the sections of the rolls of each pair being transaxially aligned perpendicular to and interengaged at said plane, the sections of longitudinally next adjacent rolls in each set being relatively offset axially and overlapping and interfitted, and each set of rolls including two groups spaced longitudinally, the sections of the rolls in each group being arranged respectively in longitudinal lines, and the aligned sections of the rolls of the two groups being offset axially a distance less than the axial length of a section and the dryer including means for flowing a stream of drying air through the cabinet.
 2. A film dryer according to claim 1 wherein each of the sets of rolls includes a plurality of main rolls, and the sections of the main rolls are all substantially of the same axial length and spaced apart a distance greater than that length but only slightly so as to provide play between interfitted sections.
 3. A film dryer according to claim 1 wherein each set includes a changeover roll between said two groups thereof, the sections of the changeover roll being of lesser axial extent than the sections of the rolls of said groups and overlapping and interfitted with the sections of the next adjacent rolls of said groups.
 4. A film dryer according to claim 3 wherein the sections of the rolls of the groups are all substantially of the same axial length, the axial offset relation of the aligned rolls of the two groups is substantially one-half that length, and the sections of the changeover roll are substantially one-half that length axially.
 5. A film dryer according to claim 1 wherein the rolls include a terminal pair closely adjacent the outlet opening, each roll includes a shaft of smaller diameter than the sections, and the dryer includes fingers at the outlet opening positioned between the sections of said terminal pair of rolls, above and below said plane, and extending along that plane beyond the peripheral surface portions of the roll sections that are most adjacent the outlet opening. 